--- /dev/null
+#!/usr/bin/env perl
+
+# Ascetic x86_64 AT&T to MASM/NASM assembler translator by <appro>.
+#
+# Why AT&T to MASM and not vice versa? Several reasons. Because AT&T
+# format is way easier to parse. Because it's simpler to "gear" from
+# Unix ABI to Windows one [see cross-reference "card" at the end of
+# file]. Because Linux targets were available first...
+#
+# In addition the script also "distills" code suitable for GNU
+# assembler, so that it can be compiled with more rigid assemblers,
+# such as Solaris /usr/ccs/bin/as.
+#
+# This translator is not designed to convert *arbitrary* assembler
+# code from AT&T format to MASM one. It's designed to convert just
+# enough to provide for dual-ABI OpenSSL modules development...
+# There *are* limitations and you might have to modify your assembler
+# code or this script to achieve the desired result...
+#
+# Currently recognized limitations:
+#
+# - can't use multiple ops per line;
+#
+# Dual-ABI styling rules.
+#
+# 1. Adhere to Unix register and stack layout [see cross-reference
+# ABI "card" at the end for explanation].
+# 2. Forget about "red zone," stick to more traditional blended
+# stack frame allocation. If volatile storage is actually required
+# that is. If not, just leave the stack as is.
+# 3. Functions tagged with ".type name,@function" get crafted with
+# unified Win64 prologue and epilogue automatically. If you want
+# to take care of ABI differences yourself, tag functions as
+# ".type name,@abi-omnipotent" instead.
+# 4. To optimize the Win64 prologue you can specify number of input
+# arguments as ".type name,@function,N." Keep in mind that if N is
+# larger than 6, then you *have to* write "abi-omnipotent" code,
+# because >6 cases can't be addressed with unified prologue.
+# 5. Name local labels as .L*, do *not* use dynamic labels such as 1:
+# (sorry about latter).
+# 6. Don't use [or hand-code with .byte] "rep ret." "ret" mnemonic is
+# required to identify the spots, where to inject Win64 epilogue!
+# But on the pros, it's then prefixed with rep automatically:-)
+# 7. Stick to explicit ip-relative addressing. If you have to use
+# GOTPCREL addressing, stick to mov symbol@GOTPCREL(%rip),%r??.
+# Both are recognized and translated to proper Win64 addressing
+# modes. To support legacy code a synthetic directive, .picmeup,
+# is implemented. It puts address of the *next* instruction into
+# target register, e.g.:
+#
+# .picmeup %rax
+# lea .Label-.(%rax),%rax
+#
+# 8. In order to provide for structured exception handling unified
+# Win64 prologue copies %rsp value to %rax. For further details
+# see SEH paragraph at the end.
+# 9. .init segment is allowed to contain calls to functions only.
+# a. If function accepts more than 4 arguments *and* >4th argument
+# is declared as non 64-bit value, do clear its upper part.
+\f
+my $flavour = shift;
+my $output = shift;
+if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
+
+open STDOUT,">$output" || die "can't open $output: $!"
+ if (defined($output));
+
+my $gas=1; $gas=0 if ($output =~ /\.asm$/);
+my $elf=1; $elf=0 if (!$gas);
+my $win64=0;
+my $prefix="";
+my $decor=".L";
+
+my $masmref=8 + 50727*2**-32; # 8.00.50727 shipped with VS2005
+my $masm=0;
+my $PTR=" PTR";
+
+my $nasmref=2.03;
+my $nasm=0;
+
+if ($flavour eq "mingw64") { $gas=1; $elf=0; $win64=1;
+ $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`;
+ chomp($prefix);
+ }
+elsif ($flavour eq "macosx") { $gas=1; $elf=0; $prefix="_"; $decor="L\$"; }
+elsif ($flavour eq "masm") { $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; }
+elsif ($flavour eq "nasm") { $gas=0; $elf=0; $nasm=$nasmref; $win64=1; $decor="\$L\$"; $PTR=""; }
+elsif (!$gas)
+{ if ($ENV{ASM} =~ m/nasm/ && `nasm -v` =~ m/version ([0-9]+)\.([0-9]+)/i)
+ { $nasm = $1 + $2*0.01; $PTR=""; }
+ elsif (`ml64 2>&1` =~ m/Version ([0-9]+)\.([0-9]+)(\.([0-9]+))?/)
+ { $masm = $1 + $2*2**-16 + $4*2**-32; }
+ die "no assembler found on %PATH" if (!($nasm || $masm));
+ $win64=1;
+ $elf=0;
+ $decor="\$L\$";
+}
+
+my $current_segment;
+my $current_function;
+my %globals;
+
+{ package opcode; # pick up opcodes
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^([a-z][a-z0-9]*)/i) {
+ $self->{op} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ undef $self->{sz};
+ if ($self->{op} =~ /^(movz)x?([bw]).*/) { # movz is pain...
+ $self->{op} = $1;
+ $self->{sz} = $2;
+ } elsif ($self->{op} =~ /call|jmp/) {
+ $self->{sz} = "";
+ } elsif ($self->{op} =~ /^p/ && $' !~ /^(ush|op|insrw)/) { # SSEn
+ $self->{sz} = "";
+ } elsif ($self->{op} =~ /^v/) { # VEX
+ $self->{sz} = "";
+ } elsif ($self->{op} =~ /movq/ && $line =~ /%xmm/) {
+ $self->{sz} = "";
+ } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) {
+ $self->{op} = $1;
+ $self->{sz} = $2;
+ }
+ }
+ $ret;
+ }
+ sub size {
+ my $self = shift;
+ my $sz = shift;
+ $self->{sz} = $sz if (defined($sz) && !defined($self->{sz}));
+ $self->{sz};
+ }
+ sub out {
+ my $self = shift;
+ if ($gas) {
+ if ($self->{op} eq "movz") { # movz is pain...
+ sprintf "%s%s%s",$self->{op},$self->{sz},shift;
+ } elsif ($self->{op} =~ /^set/) {
+ "$self->{op}";
+ } elsif ($self->{op} eq "ret") {
+ my $epilogue = "";
+ if ($win64 && $current_function->{abi} eq "svr4") {
+ $epilogue = "movq 8(%rsp),%rdi\n\t" .
+ "movq 16(%rsp),%rsi\n\t";
+ }
+ $epilogue . ".byte 0xf3,0xc3";
+ } elsif ($self->{op} eq "call" && !$elf && $current_segment eq ".init") {
+ ".p2align\t3\n\t.quad";
+ } else {
+ "$self->{op}$self->{sz}";
+ }
+ } else {
+ $self->{op} =~ s/^movz/movzx/;
+ if ($self->{op} eq "ret") {
+ $self->{op} = "";
+ if ($win64 && $current_function->{abi} eq "svr4") {
+ $self->{op} = "mov rdi,QWORD${PTR}[8+rsp]\t;WIN64 epilogue\n\t".
+ "mov rsi,QWORD${PTR}[16+rsp]\n\t";
+ }
+ $self->{op} .= "DB\t0F3h,0C3h\t\t;repret";
+ } elsif ($self->{op} =~ /^(pop|push)f/) {
+ $self->{op} .= $self->{sz};
+ } elsif ($self->{op} eq "call" && $current_segment eq ".CRT\$XCU") {
+ $self->{op} = "\tDQ";
+ }
+ $self->{op};
+ }
+ }
+ sub mnemonic {
+ my $self=shift;
+ my $op=shift;
+ $self->{op}=$op if (defined($op));
+ $self->{op};
+ }
+}
+{ package const; # pick up constants, which start with $
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^\$([^,]+)/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+
+ if ($gas) {
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{value}
+ $self->{value} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
+ $self->{value} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
+ sprintf "\$%s",$self->{value};
+ } else {
+ $self->{value} =~ s/(0b[0-1]+)/oct($1)/eig;
+ $self->{value} =~ s/0x([0-9a-f]+)/0$1h/ig if ($masm);
+ sprintf "%s",$self->{value};
+ }
+ }
+}
+{ package ea; # pick up effective addresses: expr(%reg,%reg,scale)
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ # optional * ---vvv--- appears in indirect jmp/call
+ if ($line =~ /^(\*?)([^\(,]*)\(([%\w,]+)\)/) {
+ $self->{asterisk} = $1;
+ $self->{label} = $2;
+ ($self->{base},$self->{index},$self->{scale})=split(/,/,$3);
+ $self->{scale} = 1 if (!defined($self->{scale}));
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ if ($win64 && $self->{label} =~ s/\@GOTPCREL//) {
+ die if (opcode->mnemonic() ne "mov");
+ opcode->mnemonic("lea");
+ }
+ $self->{base} =~ s/^%//;
+ $self->{index} =~ s/^%// if (defined($self->{index}));
+ }
+ $ret;
+ }
+ sub size {}
+ sub out {
+ my $self = shift;
+ my $sz = shift;
+
+ $self->{label} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
+ $self->{label} =~ s/\.L/$decor/g;
+
+ # Silently convert all EAs to 64-bit. This is required for
+ # elder GNU assembler and results in more compact code,
+ # *but* most importantly AES module depends on this feature!
+ $self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+ $self->{base} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{label}, new gas requires sign extension...
+ use integer;
+ $self->{label} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
+ $self->{label} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
+ $self->{label} =~ s/([0-9]+)/$1<<32>>32/eg;
+
+ if ($gas) {
+ $self->{label} =~ s/^___imp_/__imp__/ if ($flavour eq "mingw64");
+
+ if (defined($self->{index})) {
+ sprintf "%s%s(%s,%%%s,%d)",$self->{asterisk},
+ $self->{label},
+ $self->{base}?"%$self->{base}":"",
+ $self->{index},$self->{scale};
+ } else {
+ sprintf "%s%s(%%%s)", $self->{asterisk},$self->{label},$self->{base};
+ }
+ } else {
+ %szmap = ( b=>"BYTE$PTR", w=>"WORD$PTR", l=>"DWORD$PTR",
+ q=>"QWORD$PTR",o=>"OWORD$PTR",x=>"XMMWORD$PTR" );
+
+ $self->{label} =~ s/\./\$/g;
+ $self->{label} =~ s/(?<![\w\$\.])0x([0-9a-f]+)/0$1h/ig;
+ $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/);
+ $sz="q" if ($self->{asterisk} || opcode->mnemonic() eq "movq");
+ $sz="l" if (opcode->mnemonic() eq "movd");
+
+ if (defined($self->{index})) {
+ sprintf "%s[%s%s*%d%s]",$szmap{$sz},
+ $self->{label}?"$self->{label}+":"",
+ $self->{index},$self->{scale},
+ $self->{base}?"+$self->{base}":"";
+ } elsif ($self->{base} eq "rip") {
+ sprintf "%s[%s]",$szmap{$sz},$self->{label};
+ } else {
+ sprintf "%s[%s%s]",$szmap{$sz},
+ $self->{label}?"$self->{label}+":"",
+ $self->{base};
+ }
+ }
+ }
+}
+{ package register; # pick up registers, which start with %.
+ sub re {
+ my $class = shift; # muliple instances...
+ my $self = {};
+ local *line = shift;
+ undef $ret;
+
+ # optional * ---vvv--- appears in indirect jmp/call
+ if ($line =~ /^(\*?)%(\w+)/) {
+ bless $self,$class;
+ $self->{asterisk} = $1;
+ $self->{value} = $2;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+ }
+ $ret;
+ }
+ sub size {
+ my $self = shift;
+ undef $ret;
+
+ if ($self->{value} =~ /^r[\d]+b$/i) { $ret="b"; }
+ elsif ($self->{value} =~ /^r[\d]+w$/i) { $ret="w"; }
+ elsif ($self->{value} =~ /^r[\d]+d$/i) { $ret="l"; }
+ elsif ($self->{value} =~ /^r[\w]+$/i) { $ret="q"; }
+ elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; }
+ elsif ($self->{value} =~ /^[\w]{2}l$/i) { $ret="b"; }
+ elsif ($self->{value} =~ /^[\w]{2}$/i) { $ret="w"; }
+ elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; }
+
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ if ($gas) { sprintf "%s%%%s",$self->{asterisk},$self->{value}; }
+ else { $self->{value}; }
+ }
+}
+{ package label; # pick up labels, which end with :
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /(^[\.\w]+)\:/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ $self->{value} =~ s/^\.L/$decor/;
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+
+ if ($gas) {
+ my $func = ($globals{$self->{value}} or $self->{value}) . ":";
+ if ($win64 &&
+ $current_function->{name} eq $self->{value} &&
+ $current_function->{abi} eq "svr4") {
+ $func .= "\n";
+ $func .= " movq %rdi,8(%rsp)\n";
+ $func .= " movq %rsi,16(%rsp)\n";
+ $func .= " movq %rsp,%rax\n";
+ $func .= "${decor}SEH_begin_$current_function->{name}:\n";
+ my $narg = $current_function->{narg};
+ $narg=6 if (!defined($narg));
+ $func .= " movq %rcx,%rdi\n" if ($narg>0);
+ $func .= " movq %rdx,%rsi\n" if ($narg>1);
+ $func .= " movq %r8,%rdx\n" if ($narg>2);
+ $func .= " movq %r9,%rcx\n" if ($narg>3);
+ $func .= " movq 40(%rsp),%r8\n" if ($narg>4);
+ $func .= " movq 48(%rsp),%r9\n" if ($narg>5);
+ }
+ $func;
+ } elsif ($self->{value} ne "$current_function->{name}") {
+ $self->{value} .= ":" if ($masm && $ret!~m/^\$/);
+ $self->{value} . ":";
+ } elsif ($win64 && $current_function->{abi} eq "svr4") {
+ my $func = "$current_function->{name}" .
+ ($nasm ? ":" : "\tPROC $current_function->{scope}") .
+ "\n";
+ $func .= " mov QWORD${PTR}[8+rsp],rdi\t;WIN64 prologue\n";
+ $func .= " mov QWORD${PTR}[16+rsp],rsi\n";
+ $func .= " mov rax,rsp\n";
+ $func .= "${decor}SEH_begin_$current_function->{name}:";
+ $func .= ":" if ($masm);
+ $func .= "\n";
+ my $narg = $current_function->{narg};
+ $narg=6 if (!defined($narg));
+ $func .= " mov rdi,rcx\n" if ($narg>0);
+ $func .= " mov rsi,rdx\n" if ($narg>1);
+ $func .= " mov rdx,r8\n" if ($narg>2);
+ $func .= " mov rcx,r9\n" if ($narg>3);
+ $func .= " mov r8,QWORD${PTR}[40+rsp]\n" if ($narg>4);
+ $func .= " mov r9,QWORD${PTR}[48+rsp]\n" if ($narg>5);
+ $func .= "\n";
+ } else {
+ "$current_function->{name}".
+ ($nasm ? ":" : "\tPROC $current_function->{scope}");
+ }
+ }
+}
+{ package expr; # pick up expressioins
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /(^[^,]+)/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ $self->{value} =~ s/\@PLT// if (!$elf);
+ $self->{value} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
+ $self->{value} =~ s/\.L/$decor/g;
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ if ($nasm && opcode->mnemonic()=~m/^j/) {
+ "NEAR ".$self->{value};
+ } else {
+ $self->{value};
+ }
+ }
+}
+{ package directive; # pick up directives, which start with .
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+ my $dir;
+ my %opcode = # lea 2f-1f(%rip),%dst; 1: nop; 2:
+ ( "%rax"=>0x01058d48, "%rcx"=>0x010d8d48,
+ "%rdx"=>0x01158d48, "%rbx"=>0x011d8d48,
+ "%rsp"=>0x01258d48, "%rbp"=>0x012d8d48,
+ "%rsi"=>0x01358d48, "%rdi"=>0x013d8d48,
+ "%r8" =>0x01058d4c, "%r9" =>0x010d8d4c,
+ "%r10"=>0x01158d4c, "%r11"=>0x011d8d4c,
+ "%r12"=>0x01258d4c, "%r13"=>0x012d8d4c,
+ "%r14"=>0x01358d4c, "%r15"=>0x013d8d4c );
+
+ if ($line =~ /^\s*(\.\w+)/) {
+ $dir = $1;
+ $ret = $self;
+ undef $self->{value};
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ SWITCH: for ($dir) {
+ /\.picmeup/ && do { if ($line =~ /(%r[\w]+)/i) {
+ $dir="\t.long";
+ $line=sprintf "0x%x,0x90000000",$opcode{$1};
+ }
+ last;
+ };
+ /\.global|\.globl|\.extern/
+ && do { $globals{$line} = $prefix . $line;
+ $line = $globals{$line} if ($prefix);
+ last;
+ };
+ /\.type/ && do { ($sym,$type,$narg) = split(',',$line);
+ if ($type eq "\@function") {
+ undef $current_function;
+ $current_function->{name} = $sym;
+ $current_function->{abi} = "svr4";
+ $current_function->{narg} = $narg;
+ $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
+ } elsif ($type eq "\@abi-omnipotent") {
+ undef $current_function;
+ $current_function->{name} = $sym;
+ $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
+ }
+ $line =~ s/\@abi\-omnipotent/\@function/;
+ $line =~ s/\@function.*/\@function/;
+ last;
+ };
+ /\.asciz/ && do { if ($line =~ /^"(.*)"$/) {
+ $dir = ".byte";
+ $line = join(",",unpack("C*",$1),0);
+ }
+ last;
+ };
+ /\.rva|\.long|\.quad/
+ && do { $line =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
+ $line =~ s/\.L/$decor/g;
+ last;
+ };
+ }
+
+ if ($gas) {
+ $self->{value} = $dir . "\t" . $line;
+
+ if ($dir =~ /\.extern/) {
+ $self->{value} = ""; # swallow extern
+ } elsif (!$elf && $dir =~ /\.type/) {
+ $self->{value} = "";
+ $self->{value} = ".def\t" . ($globals{$1} or $1) . ";\t" .
+ (defined($globals{$1})?".scl 2;":".scl 3;") .
+ "\t.type 32;\t.endef"
+ if ($win64 && $line =~ /([^,]+),\@function/);
+ } elsif (!$elf && $dir =~ /\.size/) {
+ $self->{value} = "";
+ if (defined($current_function)) {
+ $self->{value} .= "${decor}SEH_end_$current_function->{name}:"
+ if ($win64 && $current_function->{abi} eq "svr4");
+ undef $current_function;
+ }
+ } elsif (!$elf && $dir =~ /\.align/) {
+ $self->{value} = ".p2align\t" . (log($line)/log(2));
+ } elsif ($dir eq ".section") {
+ $current_segment=$line;
+ if (!$elf && $current_segment eq ".init") {
+ if ($flavour eq "macosx") { $self->{value} = ".mod_init_func"; }
+ elsif ($flavour eq "mingw64") { $self->{value} = ".section\t.ctors"; }
+ }
+ } elsif ($dir =~ /\.(text|data)/) {
+ $current_segment=".$1";
+ } elsif ($dir =~ /\.hidden/) {
+ if ($flavour eq "macosx") { $self->{value} = ".private_extern\t$prefix$line"; }
+ elsif ($flavour eq "mingw64") { $self->{value} = ""; }
+ } elsif ($dir =~ /\.comm/) {
+ $self->{value} = "$dir\t$prefix$line";
+ $self->{value} =~ s|,([0-9]+),([0-9]+)$|",$1,".log($2)/log(2)|e if ($flavour eq "macosx");
+ }
+ $line = "";
+ return $self;
+ }
+
+ # non-gas case or nasm/masm
+ SWITCH: for ($dir) {
+ /\.text/ && do { my $v=undef;
+ if ($nasm) {
+ $v="section .text code align=64\n";
+ } else {
+ $v="$current_segment\tENDS\n" if ($current_segment);
+ $current_segment = ".text\$";
+ $v.="$current_segment\tSEGMENT ";
+ $v.=$masm>=$masmref ? "ALIGN(64)" : "PAGE";
+ $v.=" 'CODE'";
+ }
+ $self->{value} = $v;
+ last;
+ };
+ /\.data/ && do { my $v=undef;
+ if ($nasm) {
+ $v="section .data data align=8\n";
+ } else {
+ $v="$current_segment\tENDS\n" if ($current_segment);
+ $current_segment = "_DATA";
+ $v.="$current_segment\tSEGMENT";
+ }
+ $self->{value} = $v;
+ last;
+ };
+ /\.section/ && do { my $v=undef;
+ $line =~ s/([^,]*).*/$1/;
+ $line = ".CRT\$XCU" if ($line eq ".init");
+ if ($nasm) {
+ $v="section $line";
+ if ($line=~/\.([px])data/) {
+ $v.=" rdata align=";
+ $v.=$1 eq "p"? 4 : 8;
+ } elsif ($line=~/\.CRT\$/i) {
+ $v.=" rdata align=8";
+ }
+ } else {
+ $v="$current_segment\tENDS\n" if ($current_segment);
+ $v.="$line\tSEGMENT";
+ if ($line=~/\.([px])data/) {
+ $v.=" READONLY";
+ $v.=" ALIGN(".($1 eq "p" ? 4 : 8).")" if ($masm>=$masmref);
+ } elsif ($line=~/\.CRT\$/i) {
+ $v.=" READONLY ";
+ $v.=$masm>=$masmref ? "ALIGN(8)" : "DWORD";
+ }
+ }
+ $current_segment = $line;
+ $self->{value} = $v;
+ last;
+ };
+ /\.extern/ && do { $self->{value} = "EXTERN\t".$line;
+ $self->{value} .= ":NEAR" if ($masm);
+ last;
+ };
+ /\.globl|.global/
+ && do { $self->{value} = $masm?"PUBLIC":"global";
+ $self->{value} .= "\t".$line;
+ last;
+ };
+ /\.size/ && do { if (defined($current_function)) {
+ undef $self->{value};
+ if ($current_function->{abi} eq "svr4") {
+ $self->{value}="${decor}SEH_end_$current_function->{name}:";
+ $self->{value}.=":\n" if($masm);
+ }
+ $self->{value}.="$current_function->{name}\tENDP" if($masm && $current_function->{name});
+ undef $current_function;
+ }
+ last;
+ };
+ /\.align/ && do { $self->{value} = "ALIGN\t".$line; last; };
+ /\.(value|long|rva|quad)/
+ && do { my $sz = substr($1,0,1);
+ my @arr = split(/,\s*/,$line);
+ my $last = pop(@arr);
+ my $conv = sub { my $var=shift;
+ $var=~s/^(0b[0-1]+)/oct($1)/eig;
+ $var=~s/^0x([0-9a-f]+)/0$1h/ig if ($masm);
+ if ($sz eq "D" && ($current_segment=~/.[px]data/ || $dir eq ".rva"))
+ { $var=~s/([_a-z\$\@][_a-z0-9\$\@]*)/$nasm?"$1 wrt ..imagebase":"imagerel $1"/egi; }
+ $var;
+ };
+
+ $sz =~ tr/bvlrq/BWDDQ/;
+ $self->{value} = "\tD$sz\t";
+ for (@arr) { $self->{value} .= &$conv($_).","; }
+ $self->{value} .= &$conv($last);
+ last;
+ };
+ /\.byte/ && do { my @str=split(/,\s*/,$line);
+ map(s/(0b[0-1]+)/oct($1)/eig,@str);
+ map(s/0x([0-9a-f]+)/0$1h/ig,@str) if ($masm);
+ while ($#str>15) {
+ $self->{value}.="DB\t"
+ .join(",",@str[0..15])."\n";
+ foreach (0..15) { shift @str; }
+ }
+ $self->{value}.="DB\t"
+ .join(",",@str) if (@str);
+ last;
+ };
+ /\.comm/ && do { my @str=split(/,\s*/,$line);
+ my $v=undef;
+ if ($nasm) {
+ $v.="common $prefix@str[0] @str[1]";
+ } else {
+ $v="$current_segment\tENDS\n" if ($current_segment);
+ $current_segment = "_DATA";
+ $v.="$current_segment\tSEGMENT\n";
+ $v.="COMM @str[0]:DWORD:".@str[1]/4;
+ }
+ $self->{value} = $v;
+ last;
+ };
+ }
+ $line = "";
+ }
+
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ $self->{value};
+ }
+}
+
+sub rex {
+ local *opcode=shift;
+ my ($dst,$src,$rex)=@_;
+
+ $rex|=0x04 if($dst>=8);
+ $rex|=0x01 if($src>=8);
+ push @opcode,($rex|0x40) if ($rex);
+}
+
+# older gas and ml64 don't handle SSE>2 instructions
+my %regrm = ( "%eax"=>0, "%ecx"=>1, "%edx"=>2, "%ebx"=>3,
+ "%esp"=>4, "%ebp"=>5, "%esi"=>6, "%edi"=>7 );
+
+my $movq = sub { # elderly gas can't handle inter-register movq
+ my $arg = shift;
+ my @opcode=(0x66);
+ if ($arg =~ /%xmm([0-9]+),\s*%r(\w+)/) {
+ my ($src,$dst)=($1,$2);
+ if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
+ rex(\@opcode,$src,$dst,0x8);
+ push @opcode,0x0f,0x7e;
+ push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
+ @opcode;
+ } elsif ($arg =~ /%r(\w+),\s*%xmm([0-9]+)/) {
+ my ($src,$dst)=($2,$1);
+ if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
+ rex(\@opcode,$src,$dst,0x8);
+ push @opcode,0x0f,0x6e;
+ push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $pextrd = sub {
+ if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*(%\w+)/) {
+ my @opcode=(0x66);
+ $imm=$1;
+ $src=$2;
+ $dst=$3;
+ if ($dst =~ /%r([0-9]+)d/) { $dst = $1; }
+ elsif ($dst =~ /%e/) { $dst = $regrm{$dst}; }
+ rex(\@opcode,$src,$dst);
+ push @opcode,0x0f,0x3a,0x16;
+ push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
+ push @opcode,$imm;
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $pinsrd = sub {
+ if (shift =~ /\$([0-9]+),\s*(%\w+),\s*%xmm([0-9]+)/) {
+ my @opcode=(0x66);
+ $imm=$1;
+ $src=$2;
+ $dst=$3;
+ if ($src =~ /%r([0-9]+)/) { $src = $1; }
+ elsif ($src =~ /%e/) { $src = $regrm{$src}; }
+ rex(\@opcode,$dst,$src);
+ push @opcode,0x0f,0x3a,0x22;
+ push @opcode,0xc0|(($dst&7)<<3)|($src&7); # ModR/M
+ push @opcode,$imm;
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $pshufb = sub {
+ if (shift =~ /%xmm([0-9]+),\s*%xmm([0-9]+)/) {
+ my @opcode=(0x66);
+ rex(\@opcode,$2,$1);
+ push @opcode,0x0f,0x38,0x00;
+ push @opcode,0xc0|($1&7)|(($2&7)<<3); # ModR/M
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $palignr = sub {
+ if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
+ my @opcode=(0x66);
+ rex(\@opcode,$3,$2);
+ push @opcode,0x0f,0x3a,0x0f;
+ push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
+ push @opcode,$1;
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $pclmulqdq = sub {
+ if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
+ my @opcode=(0x66);
+ rex(\@opcode,$3,$2);
+ push @opcode,0x0f,0x3a,0x44;
+ push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
+ my $c=$1;
+ push @opcode,$c=~/^0/?oct($c):$c;
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+my $rdrand = sub {
+ if (shift =~ /%[er](\w+)/) {
+ my @opcode=();
+ my $dst=$1;
+ if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
+ rex(\@opcode,0,$1,8);
+ push @opcode,0x0f,0xc7,0xf0|($dst&7);
+ @opcode;
+ } else {
+ ();
+ }
+};
+
+if ($nasm) {
+ print <<___;
+default rel
+%define XMMWORD
+___
+} elsif ($masm) {
+ print <<___;
+OPTION DOTNAME
+___
+}
+while($line=<>) {
+
+ chomp($line);
+
+ $line =~ s|[#!].*$||; # get rid of asm-style comments...
+ $line =~ s|/\*.*\*/||; # ... and C-style comments...
+ $line =~ s|^\s+||; # ... and skip white spaces in beginning
+
+ undef $label;
+ undef $opcode;
+ undef @args;
+
+ if ($label=label->re(\$line)) { print $label->out(); }
+
+ if (directive->re(\$line)) {
+ printf "%s",directive->out();
+ } elsif ($opcode=opcode->re(\$line)) {
+ my $asm = eval("\$".$opcode->mnemonic());
+ undef @bytes;
+
+ if ((ref($asm) eq 'CODE') && scalar(@bytes=&$asm($line))) {
+ print $gas?".byte\t":"DB\t",join(',',@bytes),"\n";
+ next;
+ }
+
+ ARGUMENT: while (1) {
+ my $arg;
+
+ if ($arg=register->re(\$line)) { opcode->size($arg->size()); }
+ elsif ($arg=const->re(\$line)) { }
+ elsif ($arg=ea->re(\$line)) { }
+ elsif ($arg=expr->re(\$line)) { }
+ else { last ARGUMENT; }
+
+ push @args,$arg;
+
+ last ARGUMENT if ($line !~ /^,/);
+
+ $line =~ s/^,\s*//;
+ } # ARGUMENT:
+
+ if ($#args>=0) {
+ my $insn;
+ my $sz=opcode->size();
+
+ if ($gas) {
+ $insn = $opcode->out($#args>=1?$args[$#args]->size():$sz);
+ @args = map($_->out($sz),@args);
+ printf "\t%s\t%s",$insn,join(",",@args);
+ } else {
+ $insn = $opcode->out();
+ foreach (@args) {
+ my $arg = $_->out();
+ # $insn.=$sz compensates for movq, pinsrw, ...
+ if ($arg =~ /^xmm[0-9]+$/) { $insn.=$sz; $sz="x" if(!$sz); last; }
+ if ($arg =~ /^mm[0-9]+$/) { $insn.=$sz; $sz="q" if(!$sz); last; }
+ }
+ @args = reverse(@args);
+ undef $sz if ($nasm && $opcode->mnemonic() eq "lea");
+ printf "\t%s\t%s",$insn,join(",",map($_->out($sz),@args));
+ }
+ } else {
+ printf "\t%s",$opcode->out();
+ }
+ }
+
+ print $line,"\n";
+}
+
+print "\n$current_segment\tENDS\n" if ($current_segment && $masm);
+print "END\n" if ($masm);
+
+close STDOUT;
+
+\f#################################################
+# Cross-reference x86_64 ABI "card"
+#
+# Unix Win64
+# %rax * *
+# %rbx - -
+# %rcx #4 #1
+# %rdx #3 #2
+# %rsi #2 -
+# %rdi #1 -
+# %rbp - -
+# %rsp - -
+# %r8 #5 #3
+# %r9 #6 #4
+# %r10 * *
+# %r11 * *
+# %r12 - -
+# %r13 - -
+# %r14 - -
+# %r15 - -
+#
+# (*) volatile register
+# (-) preserved by callee
+# (#) Nth argument, volatile
+#
+# In Unix terms top of stack is argument transfer area for arguments
+# which could not be accomodated in registers. Or in other words 7th
+# [integer] argument resides at 8(%rsp) upon function entry point.
+# 128 bytes above %rsp constitute a "red zone" which is not touched
+# by signal handlers and can be used as temporal storage without
+# allocating a frame.
+#
+# In Win64 terms N*8 bytes on top of stack is argument transfer area,
+# which belongs to/can be overwritten by callee. N is the number of
+# arguments passed to callee, *but* not less than 4! This means that
+# upon function entry point 5th argument resides at 40(%rsp), as well
+# as that 32 bytes from 8(%rsp) can always be used as temporal
+# storage [without allocating a frame]. One can actually argue that
+# one can assume a "red zone" above stack pointer under Win64 as well.
+# Point is that at apparently no occasion Windows kernel would alter
+# the area above user stack pointer in true asynchronous manner...
+#
+# All the above means that if assembler programmer adheres to Unix
+# register and stack layout, but disregards the "red zone" existense,
+# it's possible to use following prologue and epilogue to "gear" from
+# Unix to Win64 ABI in leaf functions with not more than 6 arguments.
+#
+# omnipotent_function:
+# ifdef WIN64
+# movq %rdi,8(%rsp)
+# movq %rsi,16(%rsp)
+# movq %rcx,%rdi ; if 1st argument is actually present
+# movq %rdx,%rsi ; if 2nd argument is actually ...
+# movq %r8,%rdx ; if 3rd argument is ...
+# movq %r9,%rcx ; if 4th argument ...
+# movq 40(%rsp),%r8 ; if 5th ...
+# movq 48(%rsp),%r9 ; if 6th ...
+# endif
+# ...
+# ifdef WIN64
+# movq 8(%rsp),%rdi
+# movq 16(%rsp),%rsi
+# endif
+# ret
+#
+\f#################################################
+# Win64 SEH, Structured Exception Handling.
+#
+# Unlike on Unix systems(*) lack of Win64 stack unwinding information
+# has undesired side-effect at run-time: if an exception is raised in
+# assembler subroutine such as those in question (basically we're
+# referring to segmentation violations caused by malformed input
+# parameters), the application is briskly terminated without invoking
+# any exception handlers, most notably without generating memory dump
+# or any user notification whatsoever. This poses a problem. It's
+# possible to address it by registering custom language-specific
+# handler that would restore processor context to the state at
+# subroutine entry point and return "exception is not handled, keep
+# unwinding" code. Writing such handler can be a challenge... But it's
+# doable, though requires certain coding convention. Consider following
+# snippet:
+#
+# .type function,@function
+# function:
+# movq %rsp,%rax # copy rsp to volatile register
+# pushq %r15 # save non-volatile registers
+# pushq %rbx
+# pushq %rbp
+# movq %rsp,%r11
+# subq %rdi,%r11 # prepare [variable] stack frame
+# andq $-64,%r11
+# movq %rax,0(%r11) # check for exceptions
+# movq %r11,%rsp # allocate [variable] stack frame
+# movq %rax,0(%rsp) # save original rsp value
+# magic_point:
+# ...
+# movq 0(%rsp),%rcx # pull original rsp value
+# movq -24(%rcx),%rbp # restore non-volatile registers
+# movq -16(%rcx),%rbx
+# movq -8(%rcx),%r15
+# movq %rcx,%rsp # restore original rsp
+# ret
+# .size function,.-function
+#
+# The key is that up to magic_point copy of original rsp value remains
+# in chosen volatile register and no non-volatile register, except for
+# rsp, is modified. While past magic_point rsp remains constant till
+# the very end of the function. In this case custom language-specific
+# exception handler would look like this:
+#
+# EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame,
+# CONTEXT *context,DISPATCHER_CONTEXT *disp)
+# { ULONG64 *rsp = (ULONG64 *)context->Rax;
+# if (context->Rip >= magic_point)
+# { rsp = ((ULONG64 **)context->Rsp)[0];
+# context->Rbp = rsp[-3];
+# context->Rbx = rsp[-2];
+# context->R15 = rsp[-1];
+# }
+# context->Rsp = (ULONG64)rsp;
+# context->Rdi = rsp[1];
+# context->Rsi = rsp[2];
+#
+# memcpy (disp->ContextRecord,context,sizeof(CONTEXT));
+# RtlVirtualUnwind(UNW_FLAG_NHANDLER,disp->ImageBase,
+# dips->ControlPc,disp->FunctionEntry,disp->ContextRecord,
+# &disp->HandlerData,&disp->EstablisherFrame,NULL);
+# return ExceptionContinueSearch;
+# }
+#
+# It's appropriate to implement this handler in assembler, directly in
+# function's module. In order to do that one has to know members'
+# offsets in CONTEXT and DISPATCHER_CONTEXT structures and some constant
+# values. Here they are:
+#
+# CONTEXT.Rax 120
+# CONTEXT.Rcx 128
+# CONTEXT.Rdx 136
+# CONTEXT.Rbx 144
+# CONTEXT.Rsp 152
+# CONTEXT.Rbp 160
+# CONTEXT.Rsi 168
+# CONTEXT.Rdi 176
+# CONTEXT.R8 184
+# CONTEXT.R9 192
+# CONTEXT.R10 200
+# CONTEXT.R11 208
+# CONTEXT.R12 216
+# CONTEXT.R13 224
+# CONTEXT.R14 232
+# CONTEXT.R15 240
+# CONTEXT.Rip 248
+# CONTEXT.Xmm6 512
+# sizeof(CONTEXT) 1232
+# DISPATCHER_CONTEXT.ControlPc 0
+# DISPATCHER_CONTEXT.ImageBase 8
+# DISPATCHER_CONTEXT.FunctionEntry 16
+# DISPATCHER_CONTEXT.EstablisherFrame 24
+# DISPATCHER_CONTEXT.TargetIp 32
+# DISPATCHER_CONTEXT.ContextRecord 40
+# DISPATCHER_CONTEXT.LanguageHandler 48
+# DISPATCHER_CONTEXT.HandlerData 56
+# UNW_FLAG_NHANDLER 0
+# ExceptionContinueSearch 1
+#
+# In order to tie the handler to the function one has to compose
+# couple of structures: one for .xdata segment and one for .pdata.
+#
+# UNWIND_INFO structure for .xdata segment would be
+#
+# function_unwind_info:
+# .byte 9,0,0,0
+# .rva handler
+#
+# This structure designates exception handler for a function with
+# zero-length prologue, no stack frame or frame register.
+#
+# To facilitate composing of .pdata structures, auto-generated "gear"
+# prologue copies rsp value to rax and denotes next instruction with
+# .LSEH_begin_{function_name} label. This essentially defines the SEH
+# styling rule mentioned in the beginning. Position of this label is
+# chosen in such manner that possible exceptions raised in the "gear"
+# prologue would be accounted to caller and unwound from latter's frame.
+# End of function is marked with respective .LSEH_end_{function_name}
+# label. To summarize, .pdata segment would contain
+#
+# .rva .LSEH_begin_function
+# .rva .LSEH_end_function
+# .rva function_unwind_info
+#
+# Reference to functon_unwind_info from .xdata segment is the anchor.
+# In case you wonder why references are 32-bit .rvas and not 64-bit
+# .quads. References put into these two segments are required to be
+# *relative* to the base address of the current binary module, a.k.a.
+# image base. No Win64 module, be it .exe or .dll, can be larger than
+# 2GB and thus such relative references can be and are accommodated in
+# 32 bits.
+#
+# Having reviewed the example function code, one can argue that "movq
+# %rsp,%rax" above is redundant. It is not! Keep in mind that on Unix
+# rax would contain an undefined value. If this "offends" you, use
+# another register and refrain from modifying rax till magic_point is
+# reached, i.e. as if it was a non-volatile register. If more registers
+# are required prior [variable] frame setup is completed, note that
+# nobody says that you can have only one "magic point." You can
+# "liberate" non-volatile registers by denoting last stack off-load
+# instruction and reflecting it in finer grade unwind logic in handler.
+# After all, isn't it why it's called *language-specific* handler...
+#
+# Attentive reader can notice that exceptions would be mishandled in
+# auto-generated "gear" epilogue. Well, exception effectively can't
+# occur there, because if memory area used by it was subject to
+# segmentation violation, then it would be raised upon call to the
+# function (and as already mentioned be accounted to caller, which is
+# not a problem). If you're still not comfortable, then define tail
+# "magic point" just prior ret instruction and have handler treat it...
+#
+# (*) Note that we're talking about run-time, not debug-time. Lack of
+# unwind information makes debugging hard on both Windows and
+# Unix. "Unlike" referes to the fact that on Unix signal handler
+# will always be invoked, core dumped and appropriate exit code
+# returned to parent (for user notification).
projects / cassiopeia.git / blobdiff